REMOVEFILE(3) BSD Library Functions Manual REMOVEFILE(3)
NAME
removefile, removefile_state_alloc, removefile_state_free, removefile_state_get, removefile_state_set
-- remove files or directories
SYNOPSIS
#include <removefile.h>
int
removefile(const char *path, removefile_state_t state, removefile_flags_t flags);
removefile_state_t
removefile_state_alloc(void);
int
removefile_state_free(removefile_state_t state);
int
removefile_state_get(removefile_state_t state, uint32_t key, void * dst);
int
removefile_state_set(removefile_state_t state, uint32_t key, const void * value);
DESCRIPTION
These functions are used to remove a file or directory. Various levels of overwriting may be specified
to prevent other people from recovering any information about the file.
The removefile_state_alloc() function initializes a removefile_state_t object (which is an opaque data
type). This object can be passed to removefile(). removefile_state_get() and removefile_state_set()
can be used to manipulate the state (see below). The removefile_state_free() function is used to deal-locate deallocate
locate the object and its contents.
The removefile() function removes files and directories located at the named path filesystem location.
The named path location can be specified as either an absolute path or relative to the working direc-tory directory
tory of the calling process. If the state parameter is the return value from removefile_state_alloc(),
then removefile() will use the information from the state object; if it is NULL, then removefile() will
work normally, but less control will be available to the caller. The flags parameter controls deletion
options:
REMOVEFILE_RECURSIVE If the path location is a directory, then recursively delete the entire
directory.
REMOVEFILE_KEEP_PARENT The file or directory at the path location is not deleted. If specified in
conjunction with REMOVEFILE_RECURSIVE, then all of the contents of the
directory at path location will be deleted, but not the directory itself.
REMOVEFILE_SECURE_7_PASS Overwrite the file with 7 US DoD compliant passes (0xF6, 0x00, 0xFF, ran-dom, random,
dom, 0x00, 0xFF, random)
REMOVEFILE_SECURE_35_PASS Overwrite the file using 35-pass Gutmann algorithm.
REMOVEFILE_SECURE_1_PASS Overwrite with a single pass of random data
The removefile_state_get() and removefile_state_set() functions can be used to manipulate the
removefile_state_t object returned by removefile_state_alloc(). In both functions, the dst or the
value parameter's type depends on the key parameter that is passed in.
REMOVEFILE_STATE_CONFIRM_CALLBACK Get or set the callback function of type removefile_callback_t to be
called prior to file deletion.
REMOVEFILE_STATE_CONFIRM_CONTEXT Get or set any parameters of type void * that are needed for the
confirm callback function.
REMOVEFILE_STATE_ERROR_CALLBACK Get or set the callback function of type removefile_callback_t to be
called when an error is detected.
REMOVEFILE_STATE_ERROR_CONTEXT Get or set any parameters of type void * that are needed for the
error callback function.
REMOVEFILE_STATE_ERRNO Get or set the current errno of type int
REMOVEFILE_STATE_STATUS_CALLBACK Get or set the callback function of type removefile_callback_t to be
called subsequent to file deletion.
REMOVEFILE_STATE_STATUS_CONTEXT Get or set any parameters of type void * that are needed for the
status callback function.
The removefile_callback_t function pointer is defined as the following:
int (*removefile_callback_t) (removefile_state_t state, const char *path, void *context)
The return value of the callback function is given as:
REMOVEFILE_PROCEED File is deleted and removefile() continues operation as normal.
REMOVEFILE_SKIP Current file is not deleted and removefile() continues operation as normal.
REMOVEFILE_STOP Current file is not deleted and removefile() exits without continuing further.
RETURN VALUES
The family of removefile() functions returns less than 0 on error, and 0 on success.
ERRORS
removefile() will fail if:
[EACCES] The path location specifies a file or directory for which the calling process does
not have proper permissions.
[EINVAL] A callback returned an invalid return value (not REMOVEFILE_PROCEED, REMOVE-FILE_SKIP, REMOVEFILE_SKIP,
FILE_SKIP, or REMOVEFILE_STOP)
[EMLINK] The path location refers to a symbolic link.
[ENAMETOOLONG] The resource fork name of the file exceeds the maximum allowed length.
[ENOMEM] A memory allocation failed.
[ENOTEMPTY] The path location specifies a directory that contains an immutable file which cannot
be deleted.
[EPERM] The path location specifies an immutable file that cannot be deleted.
In addition, both functions may return an error from an underlying library or system call.
NOTES
Write protected files owned by another process cannot be removed by removefile(), regardless of the
permissions on the directory containing the file.
If multiple of the REMOVEFILE_SECURE_1_PASS, REMOVEFILE_SECURE_7_PASS, and REMOVEFILE_SECURE_35_PASS
flags are specified, removefile() will proceed using the flag that specifies the highest number of
overwriting passes.
EXAMPLES
/* Initialize a state variable */
removefile_state_t s;
s = removefile_state_alloc();
/* Recursively remove all files and directories while keeping parent tmp directory. */
removefile("/tmp", s, REMOVEFILE_RECURSIVE | REMOVEFILE_KEEP_PARENT);
/* Release the state variable */
removefile_state_free(s);
/* A more complex way to call removefile() -- define a callback function */
int removefile_status_callback(removefile_state_t state, const char * path, void * context) {
fprintf(stderr, "File deleted: %s", path);
return REMOVEFILE_PROCEED;
}
/* Initialize a state variable */
s = removefile_state_alloc();
/* Set callback function properties */
removefile_state_set(s, REMOVEFILE_STATE_CONFIRM_CALLBACK, removefile_confirm_callback);
removefile_state_set(s, REMOVEFILE_STATE_CONFIRM_CONTEXT, NULL);
/* Recursively remove all files and directories while keeping parent tmp directory,
calling a confirm callback prior to each file deletion. */
removefile("/tmp", s, REMOVEFILE_RECURSIVE | REMOVEFILE_KEEP_PARENT);
/* Release the state variable. */
removefile_state_free(s);
SEE ALSO
srm(1), unlink(1)
HISTORY
The removefile() API was introduced in Mac OS X 10.5.
BSD May 4, 2007 BSD
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